gonadotropic hormone

(redirected from gonadotropic)
Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to gonadotropic: gonadotropic hormones

gonadotropic hormone

(gō'nădətrŏp`ĭk) or

gonadotropin,

any one of three glycoprotein (see proteinprotein,
any of the group of highly complex organic compounds found in all living cells and comprising the most abundant class of all biological molecules. Protein comprises approximately 50% of cellular dry weight.
..... Click the link for more information.
) hormoneshormone,
secretory substance carried from one gland or organ of the body via the bloodstream to more or less specific tissues, where it exerts some influence upon the metabolism of the target tissue.
..... Click the link for more information.
 released by either the anterior pituitary glandpituitary gland,
small oval endocrine gland that lies at the base of the brain. It is sometimes called the master gland of the body because all the other endocrine glands depend on its secretions for stimulation (see endocrine system).
..... Click the link for more information.
 or the placenta (the organ in which maternal and fetal blood exchange nutrients and waste products) that have various effects upon the ovariesovary,
ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control the development of the sexual organs and the secondary sexual characteristics.
..... Click the link for more information.
 and testes (see testistestis
or testicle
, one of a pair of glands that produce the male reproductive cells, or sperm. In fetal life the testes develop in the abdomen, then descend into an external sac, the scrotum.
..... Click the link for more information.
). Gonadotropin-releasing hormone (Gn-RH) is produced and released from the hypothalamus. Gn-RH release stimulates the secretion of both follicle-stimulating hormone (FSH) and lutenizing hormone (LH) from the pituitary gland. Gn-RH is a peptide composed of ten amino acids which are synthesized in the hypothalamus (that portion of the brain nearest the pituitary). This hormone travels in the bloodstream to the anterior pituitary, where it causes the release of the gonadotropic hormones. The hormones FSH and LH inhibit the amount of Gn-RH released by a mechanism called "negative feedback." In the female, FSH causes an increase in the weight of the ovaries and encourages the growth of Graafian follicles (containing maturing eggs); in males, FSH produces spermatogenesis in the testes. In females, secretion of LH is associated with the maturation of the follicles, the manifestation of heat (or estrus), and the release of the egg from the follicle, which is transformed into a corpus luteum. In males, LH stimulates the testes to release testosterone. Sex hormones released from the ovaries and testes eventually reach the hypothalamus and help to regulate the hormonal cycle. Human chorionic gonadotropin (HCG), produced in the placenta, helps to maintain pregnancy once a fetus begins to develop. It appears in the urine in approximately the first week after the first missed menstrual period, and is the basis for two kinds of pregnancy tests; in the Ascheim-Zondek testm it causes the ovaries of an immature female rat or mouse to gain weight and produce ripened follicles, and in the Friedman test, it stimulates female rabbits to ovulate.

gonadotropic hormone

[gō¦nad·ə¦träp·ik ′hȯr‚mōn]
(biochemistry)
Either of two adenohypophyseal hormones, FSH (follicle-stimulating hormone) or ICSH (interstitial-cell-stimulating hormone), that act to stimulate the gonads.
References in periodicals archive ?
divaricata exhibit different roles in CNS, cardiovascular, gonadotropic, anti-turnout, anti-infectious and anti-oxidative activity and most recently enhancement of cholinergic activity in the nervous system.
There his group of students and collaborators engaged in the forefront of wide-ranging endocrinologic research in the isolation and study of the ovarian, gonadotropic, and adrenocorticotropic hormones.
MENOPUR is a potent gonadotropic substances capable of causing Ovarian Hyperstimulation Syndrome (OHSS) (overall IVF incidence of 3.
GONAL-f(R) is a potent gonadotropic substance capable of causing mild to severe adverse reactions, including: Ovarian Hyperstimulation Syndrome (OHSS) in women with or without pulmonary or vascular complications, and multiple births.
Chronic exposure to lead was demonstrated to affect the hypothalamo-pituitary-gonadal axis by altering serum levels of gonadotropic and androgenic hormones.
On the basis of these results, the authors postulated that BPA may disrupt the secretion of gonadotropic hormones in men, although they also acknowledged that the clinical significance of these findings is still unclear and should be further investigated (Hanaoka et al.
Estrogens also exert positive and negative feedback effects on the hypothalamopituitary axis to regulate the secretion of gonadotropic and other pituitary hormones (Hess 2003; Korach et al.
The gonadotropic hormones LH and FSH are naturally produced in the pituitary gland and play an important role in female reproduction.
In male FHMs, trenbolone-[beta] could act at the level of the hypothalamus of pituitary to depress gonadotropin-releasing hormone (GnRH) and/or gonadotropic hormone (GtH) synthesis and/or release, leading to decreased T synthesis, testicular mass, and IO distance, as was seen in this study in the males from the contaminated site.
The LHRH agonist, a Roberts' therapeutic, is a synthetic gonadotropic hormone releasing factor agonist that, due to its long-term inhibition of pituitary release of gonadotropins, can block both ovarian and testicular function.
As with all gonadotropic products, Gonal-F is capable of causing Ovarian Hyperstimulation Syndrome (OHSS) and multiple births.